I have a 1999 Grand Am GT the problems i am having are
1.The car begins to overheat, it usually gets up to 205 but now that its been 80 degrees in MN the car has gotten up to 220, the remedy i have used that has been able to bring the temp down to just over 200 is to turn the heat on full blast.
2.The coolant/antifreeze reservoir perpetually goes dry, i can not go a week without adding another jug of coolant.
3.When i turn the car off and get out the engine smells sweet. And to go along with the smell their is a milky white substance that has condensed on the oil cap.
4. The underside of the coolant reservoir cap has a crack that looks like it is permanently pushing the spring up. would this cause the cap to release the coolant when it really shouldn’t?
We are not sure how many miles the car has on it, but the previous owner estimated it to be `Well over 200,000`. The previous owner also informed us that we shouldn’t turn the ac button off.
Does any of this go together, or is it just a lot of problems that a 200,000+ mile car has to deal with?

2 Responses to “1999 Pontiac Grand Am Gt overheating”

I am going to assume the engine is a 3.1L or a 3.4L V6. If it is different you can let us know. If you are needing to add coolant, this would indicate a coolant leak. The most common would be the lower intake manifold gasket. Being able to smell the coolant burning is another indication of a coolant leak. Also if the cap is cracked, you most definitely want to replace it. To be certain where the leak is coming from, have it pressure tested. Replace the thermostat when replacing the intake gaskets as it is only a couple bucks more and you already have the coolant drained.

Once you have no leaks, the engine should run just fine and at the right temperature. As for leaving the A/C button on, this keeps the radiator fan on its highest setting. Once you have the other stuff fixed then you can look into making sure the fan even operates at lower speeds with the A/C button off.

Also, 220 degrees is nothing to be to worried about as far as causing damage. The engine would have to see above 230 degrees for you to be too concerned. None the less, it is time to fix it before it gets worse.